区段煤柱变形光纤光栅监测应用研究  

Research on the application of fiber bragg grating monitoring for deformation of coal pillar in sections

作　　者：柴敬[1,2] 王佳琪 杨健锋 高登彦 高奎英 陈建华 刘泽宇 杨磊 CHAI Jing;WANG Jiaqi;YANG Jianfeng;GAO Dengyan;GAO Kuiying;CHEN Jianhua;LIU Zeyu;YANG Lei(College of Energy Engineering,Xi’an University of Science and Technology,Xi’an 710054,China;Key Laboratory of West Mines Exploitation and Hazard Prevention of Ministry of Education,Xi’an 710054,China;China Energy Group Shendong Coal Group,Shenmu 719315,China)

机构地区：[1]西安科技大学能源学院,陕西西安710054 [2]教育部西部矿井开采及灾害防治重点实验室,陕西西安710054 [3]国家能源集团神东煤炭集团,陕西神木719315

出　　处：《煤炭科学技术》2024年第1期126-137,共12页Coal Science and Technology

基　　金：国家自然科学基金青年基金资助项目(52004203)。

摘　　要：针对近距离煤层下伏工作面过上覆遗留煤柱时,发生动静载叠加诱发强矿压显现,导致区段煤柱发生变形失稳造成人员伤亡和设备破坏。为探索基于光纤光栅实时监测区段煤柱变形发育特征,分析进、出遗留煤柱阶段矿压显现机理,将FBG、光栅应力计的光测方法相结合,结合现场实测的区段煤柱变形应力应变水平参量变化规律,研究煤柱应变空间分布规律及回采过程中工作面前方煤柱内部应变时域响应特征,验证光测方法在煤体应变水平观测的可行性。结果表明:工作面回采经过上覆遗留煤柱期间,区段煤柱顶板受集中应力影响,上部岩层块体破断并发生回转导致煤柱载荷增加,随着工作面推进覆岩断裂进一步向上传递,关键层断裂回转发生导致工作面来压,最终导致区段煤柱变形失稳。根据现场光栅应变增量幅度判断煤柱内局部变形的剧烈程度,在集中应力作用下,区段煤柱变形时发生最大应变为650×10^(-6),上覆岩层集中应力造成煤柱应变水平峰值位置为煤柱宽度11.5 m,沿煤柱宽度方向应变表现出先增加后减小然后趋于稳定的趋势,内部应变随采动过程中影响范围在5 m左右。综合研究工作面回采经过上覆遗留煤柱时应变对区段煤柱发生变形失稳的特点和规律,以及应变水平变化和煤柱物理力学性质,得到煤柱破坏的前兆特征,在外力作用下达到变形峰值前对煤柱提前进行卸压和防护的安全处理。When the coal mine passes through the overlying coal pillars in close proximity to the coal seam,the superposition of dynamic and static loads induces strong mining pressure,leading to deformation and instability of the coal pillars in the section,resulting in casual-ties and equipment damage.In order to explore the real-time monitoring of deformation and development characteristics of coal pillars in sections based on fiber Bragg grating,and analyze the mechanism of rock pressure manifestation in the stage of entering and exiting resid-ual coal pillars,the optical measurement methods of FBG and grating stress meters are combined with on-site measurement to study the spatial distribution law of coal pillar strain and the time-domain response characteristics of internal strain of coal pillars in front of the working face during the mining process,Feasibility study on verifying the optical measurement method for observing the strain level of coal bodies.The results indicate that during the process of mining the overlying coal pillars,the roof of the section coal pillars is affected by concentrated stress,and the upper rock block is broken and rotated,resulting in an increase in the load on the coal pillars.As the work-ing face advances,the overlying rock fracture further propagates upwards,and the key layer fracture recurs,causing pressure on the work-ing face.The overlying rock rotates downward,ultimately leading to deformation and instability of the section coal pillars.Based on the amplitude of on-site grating strain increment,the severity of local deformation inside the coal pillar is determined.Under the influence of concentrated stress,the maximum strength that occurs during the deformation of the section coal pillar is 650μεon the left and right sides,the concentrated stress in the overlying strata causes the peak horizontal strain of the coal pillar to be located at the 11.5 m position of the coal pillar width.The strain along the width direction of the coal pillar shows a trend of first increasing,then d

关 键 词：区段煤柱 遗留煤柱 矿压显现 光纤光栅 光栅应力计 实时监测 

分 类 号：TD323[矿业工程—矿井建设]